At some point in fall 2009, the number of lawyers with profiles on LinkedIn crossed over the 1 million mark, and stands at 1,359,590 today, according to my calculations.

With 50 million members, this shows that lawyers realize that LinkedIn is the de facto online directory of professionals, and they have made the smart move to be a part of it.

What's more, a search of Companies using the terms "law firm" turns up 4,947 results -- nearly 5,000 law firms with business profiles on LinkedIn.

The are 3,930 groups in LinkedIn with the word "law" as a part of the title.

When you set your status on LinkedIn you can now tweet it as well, amplifying it to your followers and real-time search services like Twitter Search and Bing.

There is now LinkedIn for BlackBerry, so you can walk into any interview, any customer engagement or client meeting with the ability to look up the details on over million professionals worldwide, in real-time.

There are plenty of online social networks, but LinkedIn is the one I recommend to law firms.